NCT07626658

Brief Summary

This study aims to improve how we understand and manage blood sugar responses in adults without diabetes. Even in people who appear healthy, blood sugar levels after meals can behave in different ways. These patterns may help predict future risk of diseases such as type 2 diabetes or other cardiometabolic problems. To study this, researchers at IMDEA Nutrition have developed a computer algorithm called GLIA, which uses artificial intelligence (AI) to analyze continuous glucose monitoring (CGM) data. The goal is to classify people into different "glucotypes", meaning typical patterns of how their blood sugar behaves throughout the day. These glucotypes could help tailor dietary recommendations in the future. Goals of the study

  • Do not\*have diagnosed diabetes or serious metabolic disease.
  • Agree to wear a glucose sensor for 14 days.
  • Can keep stable eating habits and record diet and physical activity. What participation involves The study lasts 3 weeks and includes 3 visits: Visit 1 - Screening (20 min):
  • Review of eligibility criteria.
  • Explanation of the study.
  • Signing informed consent.
  • Visit 2 - Initial assessment (45 min)
  • Collection of personal and health information.
  • Measurements: weight, height, waist, body composition, blood pressure.
  • Placement of a FreeStyle Libre 3 CGM sensor.
  • Instructions for:
  • Completing two 3-day food records (one each week).
  • Taking photos of all meals.
  • Reporting physical activity. Continuous monitoring (14 days) Visit 3 - Final evaluation (45 min)
  • Review of diet records.
  • Repeat measurements.
  • Blood and urine samples are collected for metabolic and molecular analyses. Meal photos are analyzed using an AI-based food recognition model. The system identifies foods and estimates nutrients (macronutrients, vitamins, minerals, glycemic index, etc.). This helps researchers understand how meals relate to blood sugar patterns. Potential benefits: Although participants may not receive direct health benefits, the study will:
  • Improve understanding of how healthy people process glucose.
  • Help identify early risk markers for metabolic diseases.
  • Contribute to developing \*\*personalized nutrition tools\*\* based on individual glucose responses. Risks: are minimal and mainly include:
  • Mild skin irritation from the CGM sensor.
  • Temporary discomfort from blood draw.

Trial Health

65
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
471

participants targeted

Target at P75+ for all trials

Timeline
28mo left

Started Jul 2026

Typical duration for all trials

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress4%
Jul 2026Dec 2028

First Submitted

Initial submission to the registry

May 27, 2026

Completed
8 days until next milestone

First Posted

Study publicly available on registry

June 4, 2026

Completed
27 days until next milestone

Study Start

First participant enrolled

July 1, 2026

Completed
1.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 1, 2028

Expected
7 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2028

Last Updated

June 4, 2026

Status Verified

June 1, 2026

Enrollment Period

1.8 years

First QC Date

May 27, 2026

Last Update Submit

June 2, 2026

Conditions

Keywords

Continuous glucose monitoring (CGM)Glucose dynamicsGlucose phenotypingGlucotypesArtificial intelligenceNutritionMachine-learningGlucose patternsPrecision nutritionChrononutritionGlycemic variabilityNutritional patternGlycemic response modelingPersonalized dietary recommendationsMultimodal metabolic phenotypingWearable glucose sensorsAI-driven health monitoringCardiometabolic healthAdults Without Diabetes

Outcome Measures

Primary Outcomes (1)

  • Glucotype Classification Derived From Continuous Glucose Monitoring Data

    The primary outcome is the glucotype assigned to each participant based on analysis of the 14-day continuous glucose monitoring (CGM) trace. Glucotypes reflect individualized patterns of glucose dynamics, capturing peak shape, amplitude, recovery, variability, and chrononutrition-related fluctuations. The classification is generated using the GLIA machine-learning algorithm, which incorporates preprocessing (normalization, artifact detection), multivariate feature extraction (including peak morphology descriptors, temporal patterns, and variability metrics), and unsupervised clustering with stability assessment. The outcome quantifies each participant's predominant glucose-response phenotype under free-living conditions and serves as the foundation for assessing associations with dietary intake, metabolic traits, and predictive modeling of glycemic responses.

    Assessed continuously over 14 days of CGM wear, with glucotype classification calculated after completion of the full 14-day glucose-monitoring period for each participant.

Secondary Outcomes (13)

  • Body mass index

    Measured during Visit 2 and Visit 3 across the 14-day monitoring period.

  • Waist circunference

    Assessed during Visit 2 and Visit 3 within the 14-day monitoring period.

  • Body Fat Percentage

    Measured during Visit 2 and Visit 3 across the 14-day monitoring period.

  • Muscle mass

    Measured during Visit 2 and Visit 3 within the 14-day CGM period.

  • Visceral Fat Index

    Measured during Visit 2 and Visit 3 over the 14-day monitoring period.

  • +8 more secondary outcomes

Other Outcomes (6)

  • Energy Intake

    Assessed across the 14-day CGM monitoring period, combining two 3-day diet records and all photographed meals.

  • Macronutrient Distribution

    Assessed across the 14-day CGM monitoring period, using two 3-day diet records plus continuous meal-photo submissions.

  • Micronutrient Intake

    Assessed throughout the 14-day CGM period, based on both 3-day diet logs and all meal photographs.

  • +3 more other outcomes

Study Arms (1)

Food_iSense Analytics Cohort

This cohort includes adults aged 18-70 years without diagnosed diabetes who undergo continuous glucose monitoring (CGM) for 14 days using a FreeStyle Libre 3 sensor. Participants complete structured dietary records, provide meal photographs for AI-based food recognition, and answer validated nutrition and physical-activity questionnaires. Anthropometry, body composition, blood pressure, and recent clinical history are collected at study visits. At the end of monitoring, fasting blood and first-morning urine samples are obtained for biochemical and molecular analyses. No therapeutic intervention is administered; instead, the study characterizes natural glucose-response patterns ("glucotypes") under free-living conditions and evaluates how diet, lifestyle, and metabolic traits relate to glycemic dynamics to support future precision-nutrition strategies.

Device: Continuous glucose monitoring using a wearable sensor (flash interstitial glucose monitor)

Interventions

The intervention consists of applying and wearing a 14-day continuous glucose monitoring (CGM) device that captures interstitial glucose every minute under free-living conditions. This wearable flash sensor is used exclusively for passive data collection; it does not provide insulin delivery, therapeutic adjustments, or real-time clinical management. What distinguishes this intervention is its integration into a multimodal data-capture system: participants simultaneously complete structured dietary records, submit standardized meal photographs for AI-based food recognition, and undergo detailed phenotyping. The CGM data are then processed through the study's proprietary GLIA algorithm to derive individualized glucose-response patterns ("glucotypes"). This combination of high-frequency glucose monitoring, dietary image analytics, and machine-learning modeling differentiates the device's use from typical clinical or self-management applications in other studies.

Food_iSense Analytics Cohort

Eligibility Criteria

Age18 Years - 70 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

The study population consists of community-dwelling adults aged 18-70 years, recruited from the general population through public advertisements, university campus postings, pharmacies, and primary care centers. Participants represent a broad, non-clinical community sample without diagnosed diabetes or severe metabolic disease. Recruitment is open to individuals living independently and able to maintain their usual daily routines. The population reflects a heterogeneous mix of sociodemographic backgrounds to ensure variability in dietary habits, lifestyle patterns, and glucose-response profiles.

You may qualify if:

  • Adults aged 18 to 70 years.
  • Willing and able to undergo 14 days of continuous glucose monitoring (CGM) using a wearable sensor.
  • Able to maintain stable dietary habits during the monitoring period.
  • Able and willing to complete dietary records, including two structured 3-day food logs.
  • Able and willing to photograph all meals during the 14-day monitoring period following instructions provided.
  • Able to keep a record of physical activity as instructed.
  • No previous diagnosis of diabetes or other serious metabolic disorders.
  • Sufficient commitment and availability to attend all study visits (screening, baseline evaluation, final evaluation).
  • Capable of providing written informed consent.

You may not qualify if:

  • Diagnosed diabetes mellitus or other serious metabolic disorders.
  • History of severe gastrointestinal, cardiovascular, or other medical conditions that may interfere with stable diet or physical activity during the study.
  • Pregnant or breastfeeding women.
  • Inability or unwillingness to comply with continuous glucose monitoring (CGM) procedures for 14 days.
  • Participants with skin conditions or allergies that prevent safe use of a CGM sensor.
  • Current participation in another clinical trial that could affect study results.
  • Use of medications that significantly alter glucose metabolism or interfere with CGM accuracy.
  • Inability to attend all scheduled study visits or complete required records (diet logs, photos, questionnaires).
  • Any condition judged by the investigators to make the participant unsuitable for the study or unable to provide informed consent.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Related Publications (8)

  • Klonoff DC, Nguyen KT, Xu NY, Gutierrez A, Espinoza JC, Vidmar AP. Use of Continuous Glucose Monitors by People Without Diabetes: An Idea Whose Time Has Come? J Diabetes Sci Technol. 2023 Nov;17(6):1686-1697. doi: 10.1177/19322968221110830. Epub 2022 Jul 20.

    PMID: 35856435BACKGROUND
  • Hengist A, Ong JA, McNeel K, Guo J, Hall KD. Imprecision nutrition? Intraindividual variability of glucose responses to duplicate presented meals in adults without diabetes. Am J Clin Nutr. 2025 Jan;121(1):74-82. doi: 10.1016/j.ajcnut.2024.10.007. Epub 2024 Dec 2.

    PMID: 39755436BACKGROUND
  • Mao Y, Tan KXQ, Seng A, Wong P, Toh SA, Cook AR. Stratification of Patients with Diabetes Using Continuous Glucose Monitoring Profiles and Machine Learning. Health Data Sci. 2022 Apr 27;2022:9892340. doi: 10.34133/2022/9892340. eCollection 2022.

    PMID: 38487483BACKGROUND
  • Hall H, Perelman D, Breschi A, Limcaoco P, Kellogg R, McLaughlin T, Snyder M. Glucotypes reveal new patterns of glucose dysregulation. PLoS Biol. 2018 Jul 24;16(7):e2005143. doi: 10.1371/journal.pbio.2005143. eCollection 2018 Jul.

    PMID: 30040822BACKGROUND
  • Zeevi D, Korem T, Zmora N, Israeli D, Rothschild D, Weinberger A, Ben-Yacov O, Lador D, Avnit-Sagi T, Lotan-Pompan M, Suez J, Mahdi JA, Matot E, Malka G, Kosower N, Rein M, Zilberman-Schapira G, Dohnalova L, Pevsner-Fischer M, Bikovsky R, Halpern Z, Elinav E, Segal E. Personalized Nutrition by Prediction of Glycemic Responses. Cell. 2015 Nov 19;163(5):1079-1094. doi: 10.1016/j.cell.2015.11.001.

    PMID: 26590418BACKGROUND
  • van Doorn WPTM, Foreman YD, Schaper NC, Savelberg HHCM, Koster A, van der Kallen CJH, Wesselius A, Schram MT, Henry RMA, Dagnelie PC, de Galan BE, Bekers O, Stehouwer CDA, Meex SJR, Brouwers MCGJ. Machine learning-based glucose prediction with use of continuous glucose and physical activity monitoring data: The Maastricht Study. PLoS One. 2021 Jun 24;16(6):e0253125. doi: 10.1371/journal.pone.0253125. eCollection 2021.

    PMID: 34166426BACKGROUND
  • Barrea L, Verde L, Colao A, Mandarino LJ, Muscogiuri G. Medical nutrition therapy for the management of type 2 diabetes mellitus. Nat Rev Endocrinol. 2025 Dec;21(12):769-782. doi: 10.1038/s41574-025-01161-5. Epub 2025 Aug 15.

    PMID: 40817355BACKGROUND
  • Safiri S, Karamzad N, Kaufman JS, Bell AW, Nejadghaderi SA, Sullman MJM, Moradi-Lakeh M, Collins G, Kolahi AA. Prevalence, Deaths and Disability-Adjusted-Life-Years (DALYs) Due to Type 2 Diabetes and Its Attributable Risk Factors in 204 Countries and Territories, 1990-2019: Results From the Global Burden of Disease Study 2019. Front Endocrinol (Lausanne). 2022 Feb 25;13:838027. doi: 10.3389/fendo.2022.838027. eCollection 2022.

    PMID: 35282442BACKGROUND

Biospecimen

Retention: SAMPLES WITH DNA

Stored plasma, blood cell fraction, and first-morning urine aliquots for future analyses.

MeSH Terms

Conditions

Prediabetic StateInsulin ResistanceGlucose Intolerance

Condition Hierarchy (Ancestors)

Diabetes MellitusGlucose Metabolism DisordersMetabolic DiseasesNutritional and Metabolic DiseasesEndocrine System DiseasesHyperinsulinismHyperglycemia

Central Study Contacts

Lidia Daimiel Ruiz, Senior Researcher

CONTACT

Víctor de la O Pascual, Junior Researcher

CONTACT

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

May 27, 2026

First Posted

June 4, 2026

Study Start

July 1, 2026

Primary Completion (Estimated)

May 1, 2028

Study Completion (Estimated)

December 1, 2028

Last Updated

June 4, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will share

De-identified individual participant data will be made available to qualified researchers upon reasonable request. All shared datasets will undergo double codification, meaning two independent pseudonymization layers are applied before external release: one ID replacing personal identifiers within IMDEA Nutrition, and a second external-use ID generated solely for data sharing. No key linking either code to participant identities will be shared. Data will be accessible only for ethically approved scientific purposes and after signing a data-sharing agreement outlining permitted use, data-security requirements, and obligations to prevent re-identification. Access will be provided through secure, controlled-transfer procedures.

Shared Documents
STUDY PROTOCOL
Time Frame
Individual participant data (IPD) and accompanying documentation will become available not before 12 months after completion of the final data analysis, anticipated to begin once all primary and secondary outcomes are fully evaluated. Data will remain accessible to qualified researchers for a minimum of 5 years following the initial release. After this period, continued availability will depend on dataset relevance, ethical approvals, and storage capacity. Access will be granted only through controlled procedures and under a signed data-sharing agreement ensuring secure use and strict protection against re-identification.